Chronic Obstructive Pulmonary Disease (COPD) comprises chronic bronchitis and emphysema. COPD is a serious progressive lung disease which makes it harder to breath. COPD currently affects over fifteen million people in the United States alone and is currently a leading cause of death worldwide. The economic and social burden of the disease is both substantial and increasing.
Chronic bronchitis is characterized by chronic cough with sputum production. The resulting airway inflammation causes eventual fibrosis of the lung airway walls, causing significant reduction in gas exchange capability of the lungs. Emphysema is characterized by the destruction of the lung parenchyma, the functioning part of the lungs. This destruction of the lung parenchyma leads to a loss of elastic recoil and tethering which maintains airway patency. Because bronchioles of the lung are not supported by cartilage like the larger airways are, they have little intrinsic support and therefore are susceptible to collapse when destruction of tethering occurs, particularly during exhalation. The loss in elastic recoil in COPD patients leads to air trapping and hyperinflation of the lungs. The result is poor respiration (gas exchange) and increased residual volume of the lungs leading to increased CO2 retention and reduced O2 supply to the alveoli of the lungs.
One existing approach to treat COPD is lung volume reduction surgery (LVRS), where a portion of diseased lung is removed surgically, for improved functioning of the remaining lung tissue. By removing the diseased portion of a lung, the remaining healthier alveoli are able to inflate more fully and lung function is improved. However, LVRS carries with it substantial risk due to its invasive nature. Another approach is to block diseased portions of the lung by blocking airways leading to these portions. However, presence of collateral airflow pathways in the lungs may decrease the effectiveness of this approach. The devices and methods of the current disclosure may enable lung volume reduction without one or more of the limitations discussed above.